Automatic relief and back-pressure valve.



PATENTED MAR. 5, `190'?.

J. V. SCHMID. AUTUMATIG RELIEF AND BACK PRESSURE VALVE.

APPLIUATION FILED SEPT.17,1906.

3 SHEETS-SHEET 2.

' Witnesses @oayza y PATBNTBD MAR. 5, 1907.

J. V. SCHMID. AUTOMATIC RELIEF AND BACK PRESSURE VALVE.`

, APPLIOATIONVPILED SEPT. 17,1906.

3 SHEETS-SHEET 3.

I @wanton Q MWI,

lUNrITED STAl- 'P Air-invr cierren.

JoHN v. soi-1Min, oi' PHILADELPHIA, PENNSYLVANIA.

l AUTomATIo RELIEF AND-BAoK-PRESSURE VALVE.

No. 846,059.v

`Specification o f I'ietters Patent. l

.Patenteamareh 19o?.

Appiiaaansiaspember 1.7.1966.' sern No. 334.991.

To a/Z whom L'mayconcern:

Be it'known that I, JOHN V. SCHMIISJ a citizen of the United States,residing in the city and county of Philadelphia, State of Penn-Sylvania, have inventedl a new land useful` Automatic Relief andBack-Pressure Valve,

' of which the fol-lowingis a specification.

My present-invention relates to automatic relief and back-pressurevalves, and `consists of a novel and simplified'. construction in whichparts are .dispensed with ywhich-'have heretofore been 'deemedessential.

It has heretofore been proposed to employ in a valve of this vcharacterastop mechanism and guide located abovethe v'alvehsaidy sto mechanismbeing carried' bythe casing vglobe and tained in the condenser, but assoon as the vacuum is lostjthe valve immediately opensand the engineexhausts into the atmosphere and continues to run non-condensing.untillthe vacuum is restored, whereupon the valve automatically closes. ltfurther consists of'a novel construction of a double-acting piston-valvewhich prevents the valve `from opening too suddenly and also preventstheclattering or hammering of the valve when vthe engine is'runningvnon-condensing. p i A It further consists of a novel construction inwliioh all of the moving partsare so located that there is nopos'sibility of their rusting or corroding due to exposure to theweather, `especially in the vertical type. p

It-further-eonsists of a novel construction of a double-acting valve inwhich means are providedfor positively seating` or unseating the valve,as desired. v It further consists of a novel construction and arranement-fof parts whereby -it is not essential t at 4the check-'valve emlo ed to admit additional fluid-pressure to t e iollowV valve shouldhavean accurate fit, since if thereis any leakagearound this valve it canonly pass tothe chambersin thefhollw valve, and if there is any leakagearoundgv the pistonlsupport through thebottom of the hollow va ve thisfluid will pass back into the inletchamber. It further consists of othernovel features of construction, all as will be hereinafter fully setforth.

Figure 1 represents a/section'al view of an'4 ,automatic relief andback-pressure valve embodying vmy invention. Fig. 2 represents asectional elevation of another embodiment thereof.' Fig 3 represents asectional elevation of another embodiment-of my invention, showin only aportion thereof. Simi ar numerals ofreference indicate correspondingparts in the figures.

Referring. to the drawings, referring first to Fig. 1, 1 4designates acasin having an;

inlet-chamber 2 and an' outlet-c amber 3.

4 designates a valve-seat which carries a spider 5, Ith'e same having anaperture therethrough of differential diameters 6 and 7.

' 8" designates a piston-support vand valve-V guide havingr a flange orshoulder 9, which is adapted-to*engage the enlarged diameter 7,Asaid."'piston-support 8 being secured in place by means of anutorsleeve `10,*which abuts againstthe shoulder 9 and has threaded orother engagementwith the piston-support 8.

11 designates a' lock-nut for the nut 10. 12'designates a passageextendincgfthrough thepis'ton-support 8, the upper en of which isenlarged, as seen atf13 in order to receive a check-valve 14 of anysuitable or conventional type.- This valve in the present instance hasribs or guides 15,eXtending therefrom, which serve to. keep the valvealways central and prevent it from leavin its seat, and-the valve isalso 'provided wit a-body 'porti-01116.

17 'designates-'a' stationary iston having annular grooves 18 therein'.his piston is m aintained in yproper position with respect to -thepiston-support 8, in the present instance by means of'acap 1 9, havingthreaded or ,otherl-'engagement with the upper end thereof, s id capbeing '20, extending therethrough.

" 21 .designates a hollow main Valve havin?, an aperture22 through thebottom thereof, adapting the same to slide on the piston-support 8,.thepiston 17 having sliding engage- -ment with the Walls, of the chamberand diprovided with an `aperture ros viding the same into two chambers-2 3 and 24, it being understood that the isto`i1i17 is of suchdimensions that the flui may leak.

therearound from the chamber 23 to the rio chamber 24, and vice versa,to a desired extent. The valve 21 is provided with a removable top orcover 25, which is secured thereto by any suitable means, said coverf25having an outwardly-projecting member 26, which is guided in' a chamber27 in the casing-cover 28, which is secured to the casinir 1 by anysuitable means, such as bolts and nuts 29 or equivalent fasteningdevices. The member 26 is provided with a chamber 30, in which theenlarged diameterl of a rod32 is mounted, the rod 32 passing through anaperture 33 in the top of said member 26 and a lso extending through astuffing-box 34, which has threaded 'or other engagement with thecasing-cover 28. The member 26 v is recessed on one side, as seen at 35,in order.

that the enlarged head 31 of the rod 32 may be readily inserted in thechamber 30.

' 36 designates a reduced end ofthe' rod or stern 32, aving .mountedthereon the block 37, which is maintained in position by means of a nut38, which has threaded engagement with the end of the stem 36. `Theblock 37 is pivoted at 39 to a handle or lever 40, said handlebeing-pivoted at 41 to a link 42, which is ulcrumed 'at 43 to the'casingcover 28. In this embodiment it is to be noted that adouble-acting valve is employed which revents'the valve from opening toosudden y and also prevents any clattering of the valve when' the engineis running noncondensing. When the engine is condensin and the vacuumhas ceased, the engine wi still continue to inject steam into theexhaustpi e 2. The steam will accumulate in this ex aust-pipe and itwill be necessary for the valvev to open.

The operation of this embodiment will be readily apparent and is asfollows: As the pressure accumulates in the exhaust-pipe 2 andunderneaththe hollow valve 21 the fluid will find its way through thepassa e 12 in the piston-support to the small chec -valve 14anderaisingthe same will pass into the chamber:24,formed between thepiston 17 and the ca y,25, it being understood that the main va ve isstill in its closed or seated position, since the accumulated pressureis as yet insufficient to raise the main valve 21. The iluid passingintov the chamber 24 will act against the valve-top 25 and materiallyassist the pressure acting against the bottom of the valve t0 raise themain valve, it being a parent that the check-valvewill allow t e steamto enter the chamber. 24 and act as a secondary power to lift the mainvalve from its seat. Without this admission of motive fluid a higherpressure'underneaththe valve would be essential and it would benecessary to increase the area of the under seat of the valve to producethe same result. In the present instance I have shown a handleoperatively connected with the rod 32, whereby the main valve may bemanually actuated passage 62.

when it is desired to have a free exhaust ofthe fluid. This handle maybe permanently located in open position, if desired, owing to the mannerin w lich it is fulcrumed.

Referring now to Fig. 2, 44 designates a valve-casing having aninlet-chamber 45 and adischarge-chamber 46,' said casing having aremovable side 4or cover 47, which is secured thereto by suitablefastening devices 48.

49 designates a spider which has extending upwardly therefrom andintegral therewith in the present instance the piston-support andvalve-guide 50, on which is placed a sleeve or bearing 51, whichterminates at a suitable' distance below the top of the support 50 inorder to serve as an abutment Jfor a stationary piston 52, mounted onthe rod 50. Any improper movement thereon of said piston is prevented bymeans of a nut 53, having threaded or other suitable engagement with thetop of the support 50 and abutting against the piston 52. The piston 52has annular grooves 54 at the outer periphery thereof.

55 designatesa hollow main valve having -an apertured bottom 56, throughwhich the piston-support or valve-guide 50 passes, the stationary piston52 dividing the interior of the hollow valve member 55 into two chambers57 and. 58. The piston 52' has a sliding fit within the valve-chambers57 and 58. The bottom of the casing 55 is removably secured thereto bycap-screws or equivalent fastening devices 59. The bottom Aof -thecasing 55 has an annular groove 60 therein, in which a tongue or lip 61of the upper casing is adapted to be seated, and thus form a water-tightjoint or seal between the parts.

62 deslgnates a passage extending through the piston-rod 50 andcommunica-ung with the chamber 57 and the, inlet-chamber 45, the lowerend of this passage 62 having seated therein a plug or closure 63, inwhich is mounted a check-valve 64, said plug having an aperture 65extending therethrough. The check valve 64 has guiding ribs or flanges66.

67 designates a conductor leading to the 68 designates a passage leadingfrom the chamber 58 and communicating with a suitable conductor 69,which in the present instance has engagement with the support 50. Itwill be apparent that in this embodiment a double-acting piston-valve isemployed with which a check-valve coacts; but in this instanceI thecheck-valve is placed at the lower end of the passage. In addition,however, I have shown connections leading to the different chambers inthe valve in order that motive fluid, ifdesired-such as compressed air,steam, or the like-may be pz'ilslsed into either of the valve-chambersat w1 It will be apparent that in this construcioo -will be seen that inthis embodiment I have dispensed with the guide-rods and guide-lugswhich arey ordinarily employed in-valves of this character above themain valve, and the main valve is guided on a central support carried bythe spider, so that all of the members of the valve-mechanism areentirely protected from @lima-tic Nor vother conditions which tend tomaterially. .reduce the eiliciency of the-valve.

It will be further noted that in this embodiment the parts may bereadily removed without disturbing the rest of the system in which thevalve is located, since the cover 47 of the casing may be readilyremoved and the hollow valve disassembled and the pistonhead removedfrom its support, so that it the valve-bearing 5l has .become worn itmaybe readily replacedv without affecting the component parts of the systemin which the valve is located.

The operation of this' embodiment is asfollows: When the vacuum in theinlet-chamber 45 isv overcome, the steam or other fluid will raise thecheck-valve 64 and permit said fluid to pass into the chamber 57, sothat whenv the pressure ol the fluid increases sufficiently the actionof the same in the chamber 57 will assist in .raising the valve, as wellas the pressure of the fluid beneath the main. valve. If it is desiredto open or close the valve by eX- ternal means, any .desired fluid underpres'- sure may be admitted to the pipes 67 and 69. If fluid-pressure ispermitted to pass through the conductor 67, it will pass into thepassage62 and cause the check-valve 64 to be posi. tively seated, thuspreventing the escape of said fluid into the inlet-chamber 45, and thisfluid will pass into the chamber 57 and acting between the stationarypiston and the upper .end of the hollow main valve will cause said mainvalve to be positively raised from its scat. It it is desired to seatthe valve, this .may be accon'iplished by admitting fluidpressure fromthe pipe 69 into the passage 68, thence to the chamber 58, and thisfluid-pres- .sure acting between the stationary piston andthe bottom ofthe valve will cause the valve to be seated in a very positive manner,

as is evident. Although in the present in,- stance I. have not shownthis valve as being adapted to be manually actuated, it will be apparentthat for the'manualactuation of this valve it is only necessary toconnect therewith a lever suitably pivoted'. If desired, the check-valvemay be dispensed on [which the main valve moves with, in which casethe/lower end of the passage 62 would be closed.

In the embodiment shown in Fig. 3, 70 designates a casing which supportsthe spider 71, the latter having extending therefrom and integraltherewith, if desired, a rod or .support 72, having a passage 73.there.-

through, although this passage may be sometimes omitted and a solid rod.or guide employed. 74 designates a valve which is adapted to coact'with the valve-seat 75, said valve hav-- ing-.a bearingA 76, which ismounted on the guide or extension 72'. The valve 74 is provided with anupwardly-extending member 77, the upper end of which is closed by asuitable cap or cover 7 S, having threaded or other engagementtherewith. Owing to the employment of a piston orblock 79, engaging thesupport 72, two chambers and 81 are formed Within the member 77. Inorder to increase the size of the chamber'SO, I have formed an annularrecess 82 in the block 79.

In this embodiment it will be seen that in a similar manner 4to thatalready described I have produced a novel construction ofy double-actingvalve in which fluid under pressure will pass through the passage 73into the chamber 80' and acting against the cover or Sis cap 78 ofthevalve 74 assist the raising ofthe 9 5 ploy auxiliary pistons in thelarger sizes or in places where it 1s inconvenient to manually operatethe free exhaust and to cause the valve to leave itsseat. the"free-exhaust valve ismore sensitive to j the conditions that existinthe exhaust-pipe than in the-devices heretofore employed; Itv is notessential'that the small check-valve employedhave a tight fit, and if;there is more or less leakage therearound it-does .not` materiallyaffect the proper working of the arts. In many cases. the verticalfree-exaust valve is open to the weather, and if a spindle is emplo edabove the valve, serving as a guide'fort e same, then the spindle isliable to be rusted or corroded in such a man- IOO Inmy construction nerthatl the proper working of the valve thereon will be materiallyaffected. From my' present construction', as shown in Fig. 2, it will beapparent that all the working'parts arelinclosed, so that the support orbearing is protected from climatic conditions..

In all the embodiments of my invention suitable levers'or other meansmaybe employed wherehv the valve may be manually y weather, the valveserves the purpose of a free-exhaust valve.

It Will be apparent that thevalve may be readily repaired or removedwhen-desired, since the casing-cover and the valve mechanism may bereadily disassembled without disturbin the other parts of the system.

It will also be apparent that in all the em- Q Abodiments of 4myinvention there is no possibility of any hammering or clattering of thevalve, owing tothe cushioning chambers formed therein and the stationarypiston en iployed. If desired, the bottom o the main valve may beperforated er formed of ribs, inwhich case the ribs or perforated.valve-bottom will .abut againstthe piston and prevent the main valvefrom leaving its seat, it being notedthat in every instance the partsmay be so perforated that thefpiston will engage the bottom of vthe mainvalve to serve asia stop to limit the upward movement of said valve, ifdesired.

In some instances, in which it is desired to employ onlycushioning-chambers within the mainivalve, the passage leading from theinlet-chamber to the interior of the main valve maybe dispensed with,and it will be apparent' that in such a construction the pistoncarriedby its support will act as a stop to limit theupward movement of saidvalve.

It will be apparent from the foregoing that I have in the presentinstance produced a novel and useful construction of valve whichembodies the features of advantage enumerated as desirable, and althoughin the present instance I have shown` and described the preferredembodiments thereof it will be apparent that they are susceptible ofmodification in various particulars `without departing from the spiritand scope of the inventionor sacrificing any of its advantages.

It will be further apparent that while in the present instance I haveshown the pistonsupport as terminating within the lhollow main valve andcarried by a spider this piston-support and valve-guide maybe'otherwisesuppbrted and still be within the scope `ofmy invention, itbeing only essential' that' this support be carried fromv below thevalve A 6o and terminate within the hollow main valve. Having thusdescribed my invention, what I claim asnew, and desire to secure byLet-v 'tersPatena is-.-

l 1. In a valve, a valve-casing having an 1n- Vlet and an outletchamber,a valve-'seat in said casing, a piston-support, a piston carriedthereby, and a hollow valve surrounding said lpiston and guided on saidsupport, said piston dividing said valve into a plurality of closedchambers.

' 2. I n a valve, a valve-casing having an inlet and an outlet chamber,a valve-seat in saidcasing, a piston-support, a piston carried thereby,and a hollow valve surrounding said piston and guided on said support,said piston dividing said valve into a plurality of closed chambers andthe upper end of saidv support terminating Within said valve.

3. In a valve, a valve-casing having an inlet and an outlet chamber, avalve-seat inv sald casing, a piston-support, a piston carried` thereby,a hollow valve .surrounding said piston and guidedfon said support, saidpiston dividing said valve into a plurality of closed chambers andhaving a passage leading from the inlet-chamber to one ofsaidvalve-chamber;

4. In avalve,- a valve-casing having an inlet and an outlet chamber, avalve-seat havling a spider, a combined stop-piston and guide supportcarried by said spider, a piston iiXed on said support, and a combinedhollow valve and double dash-pot surrounding said piston and guided bysaid support, said supporthaving a passage extending from theinlet-chamber into said hollow valve. l

5. In a valve, a casing having an inlet and an outlet chamber, avalve-seat having a spider in said casing, a piston-support carried bysaid spider, a piston fixed. on-said` support, a hollow main valvesurrounding lsaid piston and mounted'on said support, said pistondividing said main valve into two closed chambers, said support having apassage leading from the inlet-chamber to one of ICO saidvalve-chambers, and a check-valve in l said passage.

6. In a valve, a casing having an inlet and an outlet chamber, avalve-seat having a spider carried thereby in said casing, a.piston-support carried by said spider, a piston secured at the upperend of said support, a hollow main valve surrounding said-piston IIO andengaging said support, said pistoii'ljdividing said main valve into twoclosed chambers, said support having a passage therethroughcommunicating with the inlet-chamber and one of said valve-chambers, acheck-valve in said passage, and means for manually actuating said mainvalve.

7. In a valve, a casing having an inlet and an outlet chamber,y avalve-seat having a Vspider in said casing, a support'carried by saidspider, a piston removably secured to Asaid support, a hollow main valveengaging said supportv and in which said piston is mounted, said casinghaving a removable side having a chamber therein, said main valve havingan extension engaging said chamber, said piston dividing said main valveinto two closed chambers, said support having a passage leading from theinlet-chamber to one of said valve-chambers, and means engaging saidpiston for manually actuating said valve.

S. In a valve, a casing having an inlet and an outlet chamber, avalve-seat having a spider in said casing, a support carried by saidspider, a piston removably secured to said support, a hollow main valveengaging said support and in which said piston is mounted, said casinghaving a removable side having a chamber therein, said main valve havingan extension engaging said chamber, said piston dividing said main valveinto two closed chambers, said support having a passage leading from theinletchamber to one of said valve-chambers, and means for engaging saidextension for manually actuating said valve, said means being adapted topermit said valve to be automatically actuated. A

9. In a valvef, a casing having an inlet and an outlet chamber, avalve-seat having a spider Within said casing, a support carried by saidspider, a piston carried by said support, a hollow valve surroundingsaidpiston and engaging said support, said p iston dividing said valve intotwo closed chambers, said support having a passage therethrough leadingfrom the inlet-chamber to the upper of said valve-chambers, and acheck-valve in said passage at the upper end thereof.

10. In a valve, a casing having an inlet and an outlet chamber, avalve-seat havincr a spider in said casing, a support carried lby saidspider, a sleeve-lining removably mounted on said,I support, a pistonfixed on said support,'a hollow main valve surrounding said piston andengagingsaid lining, said piston d1- viding said valve into two closedchambers, said support having a passage therethrough leading from theinlet-chamber to the upper of saiduvalve-chambers, and a check-valve insaid passage.

11. In a valve, a casing having an inlet and an outlet chamber, avalve-seat having a spider in said casing, a support carried by saidspider, a piston having annular grooves therein engaging said support, ahollow mam valve in which said piston is mounted and engaging saidsupport, said piston dividing said main valve into two closed chambers,said support having a passage therethrough leading from theinlet-chamber to one of said valve-chambers, means for admittingfluidpressure to said passage, said support having a passage openinginto the other of said chambers, and means for admitting motive iiuidthereto.

12. In a valve, a casing having an inlet and an outlet chamber, avalve-seat having a .spider in said casing, a support carried by saidspider, a piston removably carried by said support, a hollow main valvesurrounding said piston and engaging said support and divided by saidpiston into two closed valve-chan'ibers, said support having a passageleading i'rom the inlet-chamber to the upper oi said valve-chambers,check-valve 1n said passage, and means intermediate said check-valve andsaid main valve for admitting Huid-pressure to the latter.

13. ln a valve, a casing having an inlet and an outlet chamber, avalve-seat havin y a spider in said easing, a support carried )y saidspider', a. piston removably secured to said support, a hollow mainvalve engaging said support and surrounding said piston and dividedthereby into two valve-chambers, said support having a passage leadingfrom the inlet-clnimber to one of said valve-chambers, a check-valve insaid passage, means for admitting Huid-pressure to said passage, saidsupport having a second passage therethrough leading to the other ofsaid valvechambers, and means for controlling the passage offluid-pressure thereto.

14. In a valve, a casing having an inlet and an outlet chamber, avalve-seat having a spider in said casing, a support carried by saidspider, a piston removably carried by said support, a hollow valvesurrounding said piston and engaging said support, said piston dividingsaid valve into a plurality of chambers, said support having a passagetherethrough leading 'from said inlet-chamber to the upper of saidvalve-chambers, a checkvalve in said passage, a pipe leading from afluid-supply to said passage, said support having a passage opening intothe lower of said chambers, and a pipe leading from a Huid-supplycommunicating with said passage. Y

15. In a valve, a valve-casing having an inlet and an outlet chamber, avalve-seat having a spider, a piston-support carried by said spider, apiston fixed on said support, and a combined hollow valve a doubledashpot surroundingsaid piston and guided by said support, said pistonserving as a stop for said valve in both directions.

16. In a valve, a valve-casing having an inlet and an outlet chamber, avalve-seat having a spider, a piston-support carried by said spider, apiston iixed on said support, and a hollow valve surrounding said pistonand guided by said support, said support having a passage extending fromthe inletchamber into said hollow valve, said piston serving as a stopfor said valve, in both directions.

17. In an automatic valve, a casing having an inlet and outlet chamber,a combined stop, guide, and piston support, a piston thereon, and acombined hollow valve-disk and double dash-pot guided on said support,the lower end of said hollow valve-disk and IOC double dash-pot engagingsaid piston when said valve-disk and double dash-pot reaches t acombined stop, guide, and piston-support,

a piston carried thereby, and a combined hollow valve-disk and doubledash-potvsurrounding said piston and guided on said suport, said pistondividing said combined holow valve-disk and double dash-pot into aplurality of chambers, the size of which vary when the valve isautomatically actuated.

19. In an automatic valve, a casing having an inlet and outlet chamber,a valve-seat having a spider supported below said seat, a combined stop,guide, and piston-siipport carried by said spider, a piston removablysecured to said support, a combined hollow valve-disk and doubledash-pot engaging said combined stop, guide and piston-support and inwhich said piston is mounted, said casing having a removable side havinga chamber therein, said combined valve-disk and'double dash-pot having apiston engaging said chamber, said piston dividing said dash-pot intotwo chambers, said support having a passage leading .from theinletehamber to the upper chamber of said dashpot, and means formanually actuating said valve-disk.

20. In an automatic valve, a casing having .an inlet and outlet chamber,a valve-seat having a spider, a combined stop, guide, and piston-supportcarried by said spider, a piston removably secured to said support, acombined hollow valve disk and double dash-pot engaging said support andin which said piston is mounted, said casing having a removable sidehaving a chamber therein, said combined valve and double dash-pot havinga piston en aging said chamber, saidv piston dividingsaic dash-pot intotwo chamers, said support having a passage leading from theinlet-cliamber to the upper chamber of the dash-pot, and means en agingsaid piston for manually actuating sai valve and dash-pot, said meansbeing adapted to per-- mit said valve to be automatically actuated.

21. In an automatic valve, a casing having an inlet and outlet chamber,a valve-seat having aspider, a combined stop, guide, and

piston-sup ort carried by said spider, a piston carrie by said support,ya combini`\d hollow valve-disk and double dash-pot surrounding saidpiston and engaging said support,

said piston dividing said dash-pot into two chambers, said supporthaving a passage` therethrough leading from the inlet-chamber to theupper chamber of said dash-pot, and an automatic check-valve in saidpassage. at. the uppei` end thereof. l

*22.A In an automatic valve, a casing-having an inlet and outletchamber, a valve-seat having a spider, a combined stop,I guide, and

piston-support carried by said spider, a sleeve removably mounted onsaid. support, a piston iixed on said support, a combined hollowvalve-disk and doubledash-pot surrounding said piston and engaging saidsleeve, said piston dividing said dash-pot into two chainbers, saidspider being supported from below said valve-seat, said support having apassage therethrough leading from the inlet-cliainber to the upperchamber of said double dashpot, and an automatic check-valve in saidpassage.

23. In an automatic and Huid-pressureactuated valve, a casing having aninlet and outlet chamber, a valve-seat having a spider supported frombelow said seat, a combined stop, guide, and iston-support carried bysaid spider, sait piston having annular grooves therein, a combinedhollow valvedisk and double dash-pot engaging said support andsurrounding said piston, said piston dividing said dash-pot into twochambers, said support having a passage therethrough leading troni theinlet-chamber to the upper chamber of said dash-pot, means for admittingiluid-pi'essuie to said passage, said support having a passage openinginto the lower chamber or said das i-pot, and means for admittingHuid-pressure thereto.`

24. In an automatic and iluid-pressure-operated valve, a casing havingan inlet and outlet chamber, a valve-seat' having a spider supportedfrom below the valve-seat, a combined stop, guide, and piston-siipportcarried b v said spider, a piston removably carried by said support, acombined hollow valve-disk and double dash-pot surrounding said pistonand engaging said support, said piston dividing said dash-pot into twochambers, said support having a passage leading from the inlet-chamberto the upper chamber of said dash-pot, an automatic check-valve in saidpassage, and means intermediate said checkvalve and the upper chamberof' said dashpotfor admit-ting Huid-pressure to said passage. 25. In anautomatic and Iluid-pressure-operatcd valve, a casing having an inletand outlet chamber, a valve-seat having a spider supported from belowsaid'seat, a combined stop, guide, and piston-support carried by saidspider, a piston removably secured to said support, a combined hollowvalve-disk and double dash-pot engaging said support and .surroundingsaid piston, said piston dividing means lor admitting fluid-pressure tosaid' passage, said su port having a second passage therethroug ileading to the lower chamber ol' said dash-pot, and means forvcontrolling the passage of fluid-pressure thereto.

26. In an automatic and fluid-pressure- IDO IIO

operated vallve, a casing having an inlet and outlet chamber, avalve-seat having a spider su orted below said seat,a combined stop, glue, and piston-support carried by said spider, a piston removably carriedby said support, a combined hollow valve-disk'and double dash-potsurroundin said piston and engaging said support, sai piston dividingsaid dash-pot into a plurality of chambers, said support having a assagetherethrough leading from said in fat-chamber to the upper chamber ofsaid dash-pot, an automatic checkvalve in said passage, a conduitleading from t a fluid-supply to said assage, said support having apassage leading from said inletchamber into the lower chamber of saiddashpot, and a conduit leading from the fluid-supply communicating withsaid second passage. .l JOHN V. SCHMID. A Witnesses: JOHN A.WIEDERSHEIM,

H. STOCKWELL FAIRBANKS.

